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Old 12-26-2017, 08:20 PM
 
Location: Omaha, Nebraska
7,678 posts, read 4,438,083 times
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Quote:
Originally Posted by Pokitobounto View Post
Now as a little summary, I, personally wouldn't buy this scope. Because it's a catadioptric Newton, and the spherical mirror, lense to increase artificially the focal is a no no for me...
Then, to reassure you, for that cheap, with an equatorial mount it's hard to find something incredibly better. Your son is a beginner so the image will be enough for him unless you have a terrible scope. But it's a Meade so it should be fine.
Meade makes great higher-end telescopes, but unfortunately their basic models are much more hit-or-miss.

But what's done is done. Now that the OP has purchased the scope, I'd recommend he seek out the help of a more experienced amateur astronomer to learn how to use it. Equatorial mounts often baffle beginners, and a little hands-on help can go a long way. OP, look up some astronomy clubs in your area if you find you need advice and help!
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Old 12-27-2017, 06:57 AM
 
Location: Near Luxembourg
1,915 posts, read 999,278 times
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Quote:
Originally Posted by Aredhel View Post
Meade makes great higher-end telescopes, but unfortunately their basic models are much more hit-or-miss.

But what's done is done. Now that the OP has purchased the scope, I'd recommend he seek out the help of a more experienced amateur astronomer to learn how to use it. Equatorial mounts often baffle beginners, and a little hands-on help can go a long way. OP, look up some astronomy clubs in your area if you find you need advice and help!
Indeed, that's easier. It's still possible to learn online too, but always longer
For 149$ a scope cannot be high end, and this one is no exception... I just think Meade is better than Seben lol but still...I m skeptical...

OP will see: if he sees comets instead of stars, there's something wrong lol

But it should be fine. I remember I could see the red spot on Jupiter with the 114/900 Paralux that was sleeping for years in the basement I remember it had eyepieces with a Japanese size (24,5 mm instead of 31,75mm today or 50.8mm). They where pretty awful, and still it gave me an incredible hype for astronomy...

I hope it ll be the same with the son of OP or... OP
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Old 12-30-2017, 08:12 AM
 
7,155 posts, read 3,907,949 times
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OP, what you bought should be fine. I would start with the low power eyepiece and seek out Jupiter, Saturn or the moon to start. Then switch to a higher magnification and see Jupiter’s moons and Saturn’s rings.
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Old 01-01-2018, 01:18 AM
 
Location: 60630
12,413 posts, read 18,372,167 times
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Quote:
Originally Posted by Pokitobounto View Post
Damn I thought my English was better than this

Well my answer is 'no'. I read too many bad reviews about catadioptric telescopes and the impossibility to collimate it transforms it into a lottery ticket.
But a beginner will not be able to know if the image is pretty or has a default. If he does, it usually means that the scope is pretty catastrophic lol. Back to the store in this case!
Then, if I remember, you bought a catadioptric telescope from a good brand, which is a good point in your favor ... I trust Meade.
Yet a rule of thumb I heard many times is: 'avoid newtonians telescopes that are 114/1000 and 127/1000'. They have a spherical mirror that is not as good as parabolic one. And they have this lense that increase the focal length and usually not with a great great quality. The sum of this reduce the sharpness of the image and the collimation... Well, I don't know how to collimate this kind of scope...

Few infos to see a little bit clearer about the object you bought and you ll have to use with your son:

The telescope you bought is a Newton with an aperture of 127mm /5inches (diameter of the primary mirror -the big one, you ll see it easily-).

There are multiple types of reflectors - they use mirrors- and refractors - they use lenses-.
You bought a Newton, the simplest one and very common because extremely efficient for a good price! Other type of construction for reflectors include Cassegrains, Schmidt-Cassegrain, Maksutov, Maksutov-Newton, Ritchey-Chretien.... In each case, the mirrors are in a different position, sometimes spherical, sometimes parabolic, sometimes closed by a meniscus corrector.. sometimes simply open like your Newton... It's an entire world of optic formulas that have advantages and defaults... I love this brave Newton telescope!

Then Diameter of the primary mirror tells you how much light the scope will gather (for the diameter, the larger the better, simple rule!). Once you leave the Moon, Mars, Venus, Jupiter, Saturn, you will understand how important it is. Deep sky objects are very discrete, hard to see specially with a polluted sky
Few variables in the scope will also impact the luminosity of the image, the reflectivity of the primary mirror and the secondary (here you don't really care, only when the mirror will have 5years of dust on itself, and you are not a pro of deep sky objects drawing... ^^) and also the width of the cross that supports the secondary mirror and makes shadow on the primary mirror. I noticed that this scope has thick ones... At least it ll be very solid lol. I don't understand why they don't make thin ones in 2017

Then comes what we call, the focal length. It's the distance from the primary mirror where the image is 'created'. Wiki is obviously more rigorous than me lol: 'For an optical system in air, it is the distance over which initially collimated (parallel) rays are brought to a focus.' (here with the primary mirror).
Literally, what a telescope does is gather the maximum quantity of light in a specific spot located at a specific distance from the primary mirror - the focal length - and then you zoom with an eyepiece on this spot (that's not a rigorous explanation lol, but it's roughly what happens) . The capacity of zoom depends on the focal length. The more it is long, the more you ll be able to zoom.
But there's an other phenomenon, the more you have a long focal length, the more you have a high ratio diameter divided by focal length (7.9 for your telescope). The less luminous the image is with the same eyepiece compare to a scope with a shorter focal ( the image will be more zoomed so less luminousz).
A ratio of 7.9 is good to start, very 'multirole'. Good point. You have a telescope that remains able to have a large field of view (to watch a good part of Andromeda galaxy for example) or zoom enough to see the cassini division on Saturn !

Now you know about diameter, focal length and their ratio.

You have to know that the magnitude of zoom is given by the number written on the eyepiece (its focal length) (usually 25mm and 10mm).
If you use a 25mm eyepiece with your scope, you ll zoom by the focal length divided by the focal of the eyepiece = 1000mm/25mm = 40times. 100times with the 10mm one... You will immediately notice that the more you zoom, the less luminous the image is, the more blurry it is, the more you ll understand that a very solid mount for the scope is important : you will barely touch the scope, everything will vibrates lol ^^.
Having an extremely sharp image is extremely difficult, it's a science. It's a mix between the best quality of mirrors, eyepieces, and the hardest to have for many of us because we cannot choose it easily...a great Stability of the atmosphere ! You ll understand very fastly too what I meant before by 'barbecue effect'. Our atmosphere is a lot of things, but not an example of stability 99% of the time. It moves, it moves a lot for a lot of reasons I won't detail, but basically when you zoom a lot with your favorite telescope, it's like watching the effect of the heat over a barbecue or a any kind of source of heat. You know it, heat changes the density of the 'air' and deviates the light so it's 'blurry'. Well you ll see that we are living on a giant barbecue (the Earth) that emit in the atmosphere the heat accumulated during the day, ofc I m talking during the night. It's invisible with a naked eyes (only stars that are blinking in the sky), but with a scope, it's easily visible. The atmosphere moves a lot, and it impacts the quality of the image drastically. That's why I told you to not watch through a window, even opened: the difference of temperature between inside and outside will create turbulences in the air that will totally ruin the image.
I also talked about the fact that a good way to gain in stability of the image is to have a scope that is at the same temperature than the atmosphere. It avoids the difference of temperature between the primary mirror and the air, so microscopic turbulences that impact the stability of the image will disappear.
In other words, forget your scope 1hour outside before watching the sky lol. It won't be 'hot' and will not create annoying turbulences because of its own heat. That's simple don't worry lol.

For the stability of the atmosphere, well cities are usually very bad... But it s like that, unless you move in the countryside or even better in altitude, you ll have to get used to it... BUT there are cold nights of winter where the sky is great even near Chicago...

Now comes the mount. You choose to buy a telescope with an equatorial mount. The best IMO. A little bit tricky to understand at the beginning... But once you get the concept, it's absolutely marvelous to use it! Mounts for scopes' are divided into two great families, altazimutal mounts and equatorial ones.

What's the difference? An Altaz moves up and down, left right, it's impossible to make simpler. When you look at an object in the sky, you ll have to 'follow' it due the rotation of the earth. With an Altaz' you ll have to mix a two-axis movement to follow for example Jupiter or the Moon. (left or right mixed with up or down).
Nothing special, it's impossible to make simpler. It has defaults for astrophotography that I won't detail.
A 'Dobson' telescope, is basically a Newton reflector with an ultra ultra simple altaz' mount designed by M. Dobson for almost nothing. The idea with a dobson mount is to have a light and stable and cheap mount, with the largest primary mirror possible! Some dues have mirrors that reach 800mm or 1meter! These are giants that can give you images you ll remember day an night!!

Now the amazing equatorial mount is three axis, because it also takes into account the position of the astronomer on the earth. How? Well.... instead of writing a novel on the forum, you can watch tutorials on YouTube . The idea is to target Polaris (here the star that indicates the north, easy to find) with one axis that will give you your latitude on the earth (the higher polaris is, the more in the north you are). Then you will be able to find an object with its coordinates and most important IMO, follow it by moving only ONE axis so it's muuuch more comfy. Again, it's hard to explain without images and only words, so check YouTube to help your son to use the mount i just checked, it's full of tutorials!

The mount you have is OK, it ll definitely vibrates but it should be acceptable. I think it's what we call an 'EQ-2'. It has a tubular tripod, good point.

Now as a little summary, I, personally wouldn't buy this scope. Because it's a catadioptric Newton, and the spherical mirror, lense to increase artificially the focal is a no no for me...
Then, to reassure you, for that cheap, with an equatorial mount it's hard to find something incredibly better. Your son is a beginner so the image will be enough for him unless you have a terrible scope. But it's a Meade so it should be fine. It has also a red dot finder that is great and easy to use. The eyepieces you ll have are basic. Nothing special, they are enough to start. Don't buy new ones if you or your son have zero hype...

Last but not least, enjoy the sky and our solar system and, ASK questions on this forum or another one if you feel that something is wrong.
It shouldn't, and you should like the view!
THANK YOU
for taking the time to write all this. I will keep this scope for now. You have been very helpful. If we feel the need to we will probably buy a better scope later on. Probably in the summer time.
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Old 01-01-2018, 01:19 AM
 
Location: 60630
12,413 posts, read 18,372,167 times
Reputation: 11880
Quote:
Originally Posted by Aredhel View Post
Meade makes great higher-end telescopes, but unfortunately their basic models are much more hit-or-miss.

But what's done is done. Now that the OP has purchased the scope, I'd recommend he seek out the help of a more experienced amateur astronomer to learn how to use it. Equatorial mounts often baffle beginners, and a little hands-on help can go a long way. OP, look up some astronomy clubs in your area if you find you need advice and help!
They actually have a class in the store we bought it from on January 6th. That's a start.
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Old 01-01-2018, 01:24 AM
 
Location: 60630
12,413 posts, read 18,372,167 times
Reputation: 11880
I was hoping I could spy on my neighbors with this scope...when my son isn't using it. But found out that's not the case.lol!!
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Old 01-01-2018, 07:51 AM
 
Location: Near Luxembourg
1,915 posts, read 999,278 times
Reputation: 1341
Quote:
Originally Posted by glass_of_merlot View Post
THANK YOU
for taking the time to write all this. I will keep this scope for now. You have been very helpful. If we feel the need to we will probably buy a better scope later on. Probably in the summer time.
No pb. I could write eternally about this...
I made a mistake tho: when I talk about focal ratio, it's not diameter divided by focal length, but focal length divided by diameter (=7.9 for you).
Don't forget, stars in the telescope should be 'round' (in the middle of the image), not like comets... A fast way to know if the optical system is aligned or not...
This class stuff on the 6th of January is great, and don't be impressed by astronomy, it's not more complicated than chess or photography lol
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Old 01-01-2018, 07:54 AM
 
Location: Near Luxembourg
1,915 posts, read 999,278 times
Reputation: 1341
Quote:
Originally Posted by glass_of_merlot View Post
I was hoping I could spy on my neighbors with this scope...when my son isn't using it. But found out that's not the case.lol!!
Image is inverted left and right and up and down?
Or you cannot make the focus because they are too close?
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Old 01-05-2018, 03:08 PM
 
Location: 60630
12,413 posts, read 18,372,167 times
Reputation: 11880
I set up the scope a couple of nights ago. I was today, during daytime, able zoom in on objects on the street. Like the bus-stop sign about 2, 2.5 blocks away. I used a 26 mm lens at first to easely find an object and make it sharp. Then I switched to 9 mm and it t got much closer. I was able to read the license plate of cars stopped at the traffic signal. Then yI set up the red dot view finder thingy...
I have yet as you already told me, been able to see anything at night from my window. Yes, that whole bbq effect I was told about
It's so damn cold outside , 3 degrees, so I don't feel like taking it outside yet. Maybe if we get a cloud free night and a nice moon I'm able to look at that from the window? Maybe? ......

Last edited by glass_of_merlot; 01-05-2018 at 04:16 PM..
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Old 01-06-2018, 10:50 AM
 
Location: Near Luxembourg
1,915 posts, read 999,278 times
Reputation: 1341
Quote:
Originally Posted by glass_of_merlot View Post
I set up the scope a couple of nights ago. I was today, during daytime, able zoom in on objects on the street. Like the bus-stop sign about 2, 2.5 blocks away. I used a 26 mm lens at first to easely find an object and make it sharp. Then I switched to 9 mm and it t got much closer. I was able to read the license plate of cars stopped at the traffic signal. Then yI set up the red dot view finder thingy...
I have yet as you already told me, been able to see anything at night from my window. Yes, that whole bbq effect I was told about
It's so damn cold outside , 3 degrees, so I don't feel like taking it outside yet. Maybe if we get a cloud free night and a nice moon I'm able to look at that from the window? Maybe? ......
Well,

To the last question I ll answer 'yes'. Because yes, you 'can'
You can watch the moon, you ll see it.

Will the image be pretty? No. Hell no. At least compared to the image given by a scope outside and on temperature after an hour outside.
Behind the window you ll mix ultra strong turbulences and the diffraction of the light due to the passage of the light through the glass of the window (catastrophic).
If you open the window, turbulences will be really monstrous...

So yes, you ll see ^^ badly but you ll see. But you ll be able to use 10% of the capacity of your telescope

I also watched through windows when I was ultra lazy, Venus, Jupiter, Saturn, it was pretty ultra catastrophic. But I loved it anyway
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